1. Field of Invention
This invention relates generally to dispensing devices, and more specifically to dispensing devices for viscous materials. The viscous material to be dispensed with the instantly claimed device can be packaged in either collapsible form, a form in which the viscous material is present in a cartridge, or bulk form.
2. Description of Related Art
Dispensing devices for the application of various viscous material products such as caulking materials, grease, automotive windshield sealant, dual component reactive resins, adhesives, sealants, and the like, are well known throughout many industries. Such dispensing devices ideally allow the viscous material to be applied in an accurate, mess-free, and waste-free manner.
Dispensing devices are often in the form of a dispensing gun, or caulking gun. Dispensing devices generally include a squeezable handle and trigger assembly which is operative for advancing the pistons of the dispensers and for maintaining the pistons in advanced positions when the trigger portions of the dispenser devices are released. The viscous materials can be packaged in a variety of forms; some of the most common are cartridge form, collapsible form, and bulk form.
Cartridges are most often designed with a nozzle through which a viscous material composition can be extruded. These cartridges were adapted to be loaded into dispensing devices equipped with mechanisms to push the sealant composition out of the cartridge package. Cartridges, depending on the kind of storage required for the viscous material composition, are generally made from paper, foiled lined paper, plastic, and various kinds of molded and laminated constructions.
The cartridges are typically tubes having a sealed dispensing outlet, such as a conical tip, disposed on one end, with the other end being open for receiving a plunger mechanism or the like from the dispensing device. Just inside the cartridge's open end is a slidably-sealed, axially-movable piston, disc, or the like. For use, the cartridge is placed in a retaining/dispensing section of the dispensing device, and the plunger is brought into contact with the piston. When a user desires to dispense product, the cartridge's dispensing outlet is unsealed, and the plunger is forced against the piston. This forces the piston axially down the tube and against the product, which in turn is dispensed through the dispensing outlet.
Collapsible tubes are also popular containers for viscous materials. Collapsible packaging has been known in the trade for many years, and offers the benefits of providing good shelf stability for the contained chemicals, low package cost, and minimal packaging waste. Collapsible packages are generally known in the art as a “sausage” or “chub.” Collapsible packaging has a collapsible wall that is, typically, sealed at each end. While collapsible package can be used to contain non-reactive viscous material products, the collapsible package is typically moisture impervious, thus allowing the collapsible package to contain reactive viscous material products also (typically reactive viscous material products are ones that react when exposed to humidity in the air).
Bulk forms of the viscous material may be used with dispensing devices which have a dispensing chamber adapted to be filled directly with the bulk viscous material. Moreover, all of these options (i.e., cartridge, bulk form, and collapsible form) can be employed in dual component dispensing devices as well as in single component dispensing devices.
A difficulty arises because the different forms of packaging of the viscous material, e.g. bulk form, cartridge form, or collapsible form, has heretofore required the configuration of the dispensing device to be changed, and often requires the removal and/or replacement of components of the dispensing device. These components can easily become lost. Therefore there exists a need in the art for a dispensing device for dispensing viscous materials wherein the dispenser is convertible to a form which dispenses viscous material packaged in either collapsible form, cartridge form, or bulk form, wherein the components necessary for the conversion of the device to dispense viscous material packaged in collapsible form, cartridge form, or bulk form are retained within the body of the dispensing device, and more preferably are retained on the piston rod, to prevent loss of the components necessary for conversion of the dispensing device to dispense viscous material packaged in either collapsible form, cartridge form, or bulk form.
All references cited herein are incorporated herein by reference in their entireties.